Solar Dhw Heating - Viessmann VITOTRONIC 200 Service Instructions Manual

Function description
DHW heating

Solar DHW heating

■ Via the solar control function integra-
ted into the heat pump control unit.
or
■ Via the external Vitosolic solar control
unit.
Installation and service instruc-
tions, Vitosolic
Integral solar control function
Control takes place based on the tem-
perature differential between the collec-
tor temperature sensor and the cylinder
temperature sensor.
Position of the cylinder temperature sen-
sor:
■ Bottom of the DHW cylinder.
Note
In this case, the temperature sensor is
then unavailable for any other func-
tion.
or
■ In the solar return.
Note
If both temperature sensors are connec-
ted, the higher value is evaluated.
The solar circuit pump starts when the
temperature differential exceeds the
value in parameter "Start hysteresis
solar circuit pump 7A02".
24
(cont.)
The solar circuit pump stops if:
■ The temperature differential falls
below the value in parameter "Stop
hysteresis solar circuit pump
7A03".
■ The "Max. DHW temperature 6006"
is reached.
■ Short circuit/lead break of the collector
or cylinder temperature sensor.
Suppressing of DHW cylinder reheat-
ing
The "Set DHW temperature 6000" is
reduced by 5 K during solar DHW heat-
ing.
Calculation
See parameter "Flow rate solar circuit
for calculating solar yield 7A07".
Recirculation
Low collector temperatures can result in
unwanted recirculation within the solar
circuit if the check valve in the solar cir-
cuit is faulty.
Display of the message "A4 Check
valve" is activated by setting parameter
"Display message incorrect circula-
tion 7A09".